Control of Corn Rootworm Larvae, 1977

Experimental soil insecticides were evaluated at Urbana and Macomb, Illinois during 1977. XL-45A was planted at Urbana on May 11, 12, and 25, and VH272 was planted at Macomb on May 16 and 17. The experiments were randomized blocks with 3 replicates at Urbana and 4 replicates at Macomb. Individual plots were single rows approximately 90 ft long. Granular treatments were applied by use of a Gandy applicator on single International unit planters. Band applications were applied using a 7 in. Gandy RoBander and the bander was placed 1/2 the distance between planter shoe and press wheel. No insecticide was placed on the seed but the insecticide was incorporated into the upper inch of soil. Furrow applications were applied by placing the insecticide directly on the seed in the shoe. Basal applications were made on June 1 at Urbana and June 6 at Macomb. Two tubes from the applicator were used to deliver 1/2 of each granular treatment to each side of the row as a post-emergence treatment. All basals were hand incorporated. Sprays using emulsifiable formulations were applied by a closed air pressure system. A 6 in. band of spray placed in a similar location as the granules, delivered 13 gal/acre at 30 psi at approximately 3 mph with fan jet nozzle No. 9502E. The experiments were evaluated as plants/50 ft row, root damage (Iowa 1-6 scale), and percent lodged. Means were compared at 5% level.